Escort 9500I Radar Detector User Manual


 
23
How Laser Works
How Laser (Lidar) Works
Laser speed detection is actually LIDAR
(Light Detection and Ranging). LIDAR
guns project a beam of invisible infrared
light. The signal is a series of very short
infrared light energy pulses which move
in a straight line, reflecting off your car
and returning to the gun. LIDAR uses
these light pulses to measure the distance
to a vehicle. Speed is then calculated by
measuring how quickly these pulses are
reflected given the known speed of light.
LIDAR (or laser) is a newer technology
and is not as widespread as conventional
radar, therefore, you may not encounter
laser on a daily basis. And unlike radar
detection, laser detection is not prone to
false alarms. Because LIDAR transmits a
much narrower beam than does radar, it is
much more accurate in its ability to
distinguish between targets and is also
more difficult to detect. AS A RESULT,
EVEN THE BRIEFEST LASER ALERT
SHOULD BE TAKEN SERIOUSLY. .
There are limitations to LIDAR
equipment. LIDAR is much more sensitive
to weather conditions than RADAR, and a
LIDAR gun’s range will be decreased by
anything affecting visibility such as rain,
fog, or smoke. A LIDAR gun cannot
operate through glass and it must be
stationary in order to get an accurate
reading. Because LIDAR must have a clear
line of sight and is subject to cosine error
(an inaccuracy, which increases as the
angle between the gun and the vehicle,
increases) police typically use LIDAR
equipment parallel to the road or from an
overpass. LIDAR can be used day or night.